CVE-2025-14969: Hibernate Reactive DoS Vulnerability

CVE-2025-14969 Overview

A flaw was found in Hibernate Reactive that allows remote attackers to cause a Denial of Service (DoS) condition through database connection pool exhaustion. When an HTTP endpoint is exposed to perform database operations, a remote client can prematurely close the HTTP connection, leading to leaked connections from the database connection pool. This resource exhaustion vulnerability can ultimately render the application unable to process legitimate database requests.

Critical Impact

Remote attackers can exhaust database connection pools by repeatedly initiating and prematurely closing HTTP connections, causing service degradation or complete denial of service for applications using Hibernate Reactive.

Affected Products

• Hibernate Reactive (affected versions not specified)
• Applications exposing HTTP endpoints for database operations via Hibernate Reactive
• Java/Jakarta EE applications using reactive database connectivity

Discovery Timeline

• 2026-01-26 - CVE CVE-2025-14969 published to NVD
• 2026-01-27 - Last updated in NVD database

Technical Details for CVE-2025-14969

Vulnerability Analysis

This vulnerability falls under CWE-772 (Missing Release of Resource after Effective Lifetime), which describes a condition where the software does not release allocated resources after they have been effectively used. In the context of Hibernate Reactive, when a client establishes an HTTP connection to an endpoint that performs database operations and then abruptly terminates that connection, the associated database connection may not be properly released back to the connection pool.

The attack can be executed over the network and requires low privileges to initiate. While the immediate impact is limited to availability (no confidentiality or integrity impact), the cumulative effect of multiple connection leaks can completely exhaust the connection pool, preventing legitimate users from accessing database resources.

Root Cause

The root cause of this vulnerability lies in improper resource management within Hibernate Reactive's connection handling mechanism. When an HTTP request triggers a database operation through Hibernate Reactive, a connection is acquired from the pool. If the HTTP connection is closed prematurely by the client before the database operation completes or before proper cleanup occurs, the database connection may remain in a "borrowed" state and never be returned to the pool.

This behavior indicates a missing or inadequate implementation of connection cleanup handlers that should trigger when HTTP connections are unexpectedly terminated. The reactive nature of the framework, which relies on asynchronous operations and callbacks, may complicate proper resource cleanup when the expected completion flow is interrupted.

Attack Vector

The attack exploits the network-accessible nature of HTTP endpoints backed by Hibernate Reactive database operations. An attacker can execute this attack through the following mechanism:

The attacker initiates multiple HTTP requests to endpoints that trigger database operations. Before these operations complete, the attacker forcefully terminates the TCP connections. Each aborted connection potentially leaks one database connection from the pool. By repeating this process, the attacker can systematically drain the entire connection pool.

This attack is particularly effective because it requires minimal resources from the attacker's perspective—simply opening and closing TCP connections—while consuming valuable server-side resources. The attack can be amplified by using multiple source IPs or by automating the connection/disconnection cycle at high frequency.

Detection Methods for CVE-2025-14969

Indicators of Compromise

• Unusual patterns of incomplete HTTP requests to database-backed endpoints
• Rapidly increasing count of active database connections approaching pool maximum
• Connection pool exhaustion errors in application logs
• Elevated rate of client-initiated connection resets (TCP RST packets)

Detection Strategies

• Monitor database connection pool metrics for sustained high utilization or exhaustion events
• Implement alerting on connection pool timeout exceptions in application logs
• Track HTTP connection lifecycle metrics, specifically looking for abnormal ratios of incomplete requests
• Correlate network traffic patterns with database connection pool behavior

Monitoring Recommendations

• Configure connection pool monitoring with thresholds for active connections and wait times
• Enable detailed logging for Hibernate Reactive connection acquisition and release events
• Implement application performance monitoring (APM) to track database connection lifecycle
• Set up network-level monitoring for abnormal connection patterns from specific source IPs

How to Mitigate CVE-2025-14969

Immediate Actions Required

• Review and apply any available patches from Hibernate Reactive maintainers
• Implement connection pool timeout configurations to automatically reclaim stale connections
• Consider implementing rate limiting on endpoints that perform database operations
• Monitor connection pool utilization closely and set up alerts for abnormal patterns

Patch Information

Consult the Red Hat CVE-2025-14969 Advisory for official patch information and updates. Additional technical details are available in Red Hat Bug Report #2423822. Check with your Hibernate Reactive distribution for the latest security updates addressing this connection leak issue.

Workarounds

• Configure aggressive connection validation and eviction policies in your connection pool (e.g., HikariCP maxLifetime, idleTimeout)
• Implement connection pool overflow protection by setting appropriate maximumPoolSize limits
• Add application-level timeout handling to ensure database operations complete within defined bounds
• Consider implementing a circuit breaker pattern to protect against connection pool exhaustion

# Example HikariCP configuration for connection pool hardening
# Add to application.properties or equivalent configuration

# Maximum pool size - adjust based on your database capacity
quarkus.datasource.reactive.max-size=20

# Connection idle timeout (milliseconds)
quarkus.datasource.reactive.idle-timeout=PT10M

# Connection acquisition timeout
quarkus.datasource.reactive.acquisition-timeout=PT5S